Buffered aldehyde fixation composition

ABSTRACT

The process of fixing formaldehyde on cellulose or a cellulose ester with the aid of a carbamate and using glycolic acid in the catalyst system is improved by including a buffering agent. Preferably there is also included a hexitol as a scavenger for unreacted formaldehyde.

United Stafies Patent Inventors James 1?. Cotton Columbus, 68.; John W. Reed, Shawmut; Water C. Monk, Fairfax, both of Ala. Appl. No. 762,366 Filed Sept. 16, 1968 Patented Nov. 23, 1971 Assigncc West Polnt-Pepperell, Inc.

West Polnt, Ga.

BUFFERED ALDEHYDE FIXATION COMPOSITION 26 Claims, No Drawings US. Cl 8/1 16.4, 8/116.2, 8/116.3, 8/129, 8/1 15.7, 260/230, 260/231 Int. Cl D06m13/34, D06m 13/40 Field of Search 8/1 16.4,

References Cited UNITED STATES PATENTS 3,196,036 7/1965 Cotton et al. 8/116.3 X 3,420,696 1/1969 Cotton et a1. 8/1 16.3 X

Primary E.raminerGeorge F. Lesmes Assistant Examiner-J. Cannon Anorne vCushman, Darby & Cushman ABSTRACT: The process of fixing formaldehyde on cellulose or a cellulose ester with the aid of a carbamate and using glycolic acid in the catalyst system is improved by including a buffering agent. Preferably there is also included a hexitol as a scavenger for unreacted formaldehyde.

BUFFERED ALDEHYDE FIXATllON COITION The present invention is directed to an improvement in the process of fixing an aldehyde on cellulose using a carbamate carrier as disclosed in Cotton et al. application 451,033 filed Apr. 26, 1965 now US. Pat. No. 3,420,696, issued Jan. 7, 1969.

As set forth in Cotton et al. the fixation is normally carried out using an acid catalyst. Glycolic acid works well in the Cotton et al. procedure but unfortunately has a tendency to deteriorate cellulosic materials such as cotton for example.

Accordingly it is an object of .the present invention to develop an improved procedure for utilizing glycolic acid as the acid catalyst in the fixation of an aldehyde on a cellulosic material.

Another object is to which retain their wash degree.

A further object is to scavenge unreacted formaldehyde from the treated cellulosic fabric.

Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed prepare cellulose containing fabrics and wear properties to an outstanding while indicating preferred embodiments of the invention, are only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

It has now been found that these objects can be attained by treating cellulose or a cellulose ester having residual hydroxyl groups with an aqueous mixture of the finished fabric and aids in odor control.

As stated above it is critical that the system contain a buffer. Glycolic acid is known to self condense to form polyglycolides when glycolic acid is used in the Cotton et al. process without bufiering, the fabric becomes highly acidic on standing as moisture is absorbed. Pickup of moisture apparently allows hydrolysis of the polyglycolides to glycolic acid. This hydrolysis appears to be self-catalyzing. The use of the buffers prevents the generation of acidity on standing.

The cellulose can be in the form of cotton, alpha cellulose,

viscose rayon, or paper. As cellulose esters, there can be employed cellulose acetate, e.g. 38 percent acetate content, cellulose acetate butyrate and cellulose acetate-propionate.

The cellulose material can be blended with synthetic fibers such as polyesters, e.g. polyethylene terephthalates, acrylic fibers, e.g. polyacrylonitrile, acrylonitrile-vinyl chloride (85: 1 5 or :85), nylon, e.g. polymeric hexamethylene adipamide or polymeric caprolactam, polypropylene, ethylenepropylene copolymer, spandex (polyurethane fibers), vinyl chloride-vinyl acetate (e.g. 87:13), A particularly NCOOR,

groups can be employed carbamate, ethyl carbamate, propylcarbamate, isopropyl carbamate, butyl carbamate, amyl carbamate, hexyl carbamate, isooctyl carbamate, octyl carbamate, decyl carbamate, isodecyl carbamate, dodecyl carbamate, cylohexyl carbamate, octadecyl carbamate, phenyl carbamate, o-tolyl carbamate, p-tolyl carbamate, m-tolyl carbamate, p-butylphenyl carbamate, 2-naphthyl carbamate, beta-naphthyl carbamate, 2,4-xylyl carbamate, N-phenyl isopropyl carbamate, N-phenyl phenyl carbamate, N-p-tolyl ethyl carbamate, N -phenyl methyl carbamate, N-phenyl ethyl carbamate, N-methyl phenyl carbamate, N-ethyl phenyl carbamate, N-methyl methyl carbamate, N-methyl ethyl carbamate, N-methyl decyl carbamate, N-ethyl methyl carbamate, N-ethyl ethyl carbamate, N- dodecyl methyl carbamate, N-butyl cyclohexyl carbamate, N,N-dethyl ethyl carbamate, N,N-dimethyl ethyl carbamate, N,N-diethyl methyl carbamate, N,N-diphenyl methyl carbamate, 2-hydroxyethyl carbamate, 3-hydroxypropyl carbamate, 2-hydroxypropyl carbamate, Z-hydroxybutyl carbamate, 4- hydroxybutyl carbamate, methoxyethyl carbamate, ethoxyethyl carbamate, propoxy-ethyl carbamate, methoxypropyl carbamate. Of course mixtures of carbamates can be employed, e.g. the eutectic mixture of 52 percent ethyl carbamate and 48 percent methyl carbamate. The preferred carbamates are methyl carbamate and ethyl carbamate.

The temperature of heating the product in order to fix the formaldehyde to the cellulosic material can be widely varied, e.g. from to 400 F. Temperatures of 180 to 300 F. are usually employed but the temperature is not critical. The use of a partial vacuum is recommended when drying and curing at temperatures in the order of 125 F.

Normally there is employed at least 0.1 percent, and more preferably at least 0.3 percent by weight of methyl carbamate, for example in the aqueous treating solution or dispersion, or equivalent molar percentage of other carbamates. Desirably at least 0.5

of carbamate, e.g. l to 5 percent or more of methyl carbamate in the aqueous mixture can be used but normally the improvement obtained by using over 1 percent of the carbamate does not justify the increase in cost.

Unless otherwise indicated all parts and percentages are by weight.

The aldehyde is employed in the aqueous system in an amount normally between 1 and 8 percent thereof although as much as 10 or 15 percent or more of formaldehyde can be used if relatively large amounts of formaldehydes are to be fixed onto the cellulose. Desirably the formaldehyde is employed in an amount of at least 2 moles and preferably at least 3 moles per mole of carbamate and can be employed in an amount of at least 3 moles per mole of carbamate and can be employed in an amount as much as 60 moles or even 100 moles per mole of carbamate.

When treating cotton, alpha cellulose and paper there is usually employed an aqueous mixture containing 1.25-4 percent formaldehyde, in order to fix 0.25-1.25 percent formaldehyde, on the treated material. When treating rayon and cellulose esters there usually is employed an aqueous mixture containing 2.5-8.0 percent formaldehyde, in order to fix 0.5-2.5 percent fon'naldehyde, onto the treated material.

The glycolic acid bath through which the cotton or other cellulosic material is passed generally contains a water soluble polyvalent metal salt catalyst as well to accelerate the reaction of the formaldehyde and cellulose although such salts can be omitted. Typical examples of such salts are magnesium chloride, calcium chloride, zinc nitrate, zinc chloride, zinc fluoborate (which gives excellent scorch protection), zinc silicofluoride, magnesium nitrate, magnesium fluoborate, aluminum chloride, aluminum bromide, magnesium sulfate, alualuminum sulfate, paper maker's alum, zinc bromide, magnesium bromide, zinc iodide, magnesium iodide, zinc fluoride, zirconium oxychloride, zirconium oxybromide, titanium tetrachloride, titanium tetrabromide, zinc sulfate, calcium sulfate, barium chloride, strontium chloride, barium bromide, chromic chloride. ferric chloride, ferric sulfate, cupric chloride, ferric bromide, chromic sulfate, cobaltic chloride, nickelous chloride, stannic chloride. Only a small amount of such salts is normally used.

The normal procedure for applying the formaldehyde and carbamate containing aqueous mixture to the material is to pass a fabric, fibers, sheet or continuous yarn through the aqueous mixture, and then to run the thus impregnated material through squeeze rolls to remove excess solution. in the case of yarn, the procedure employed can be to pass the aqueous mixture through packages of the yarn in a kier.

Of course there can be added to the aqueous mixture conventional additives such as wetting agents, hand modifier, softeners, lubricants, brighteners, and the like.

The process fixes formaldehyde on the base material, for example on cotton yarn or fabric with considerable reduction in loss of strength as compared with conventional resin finishing processes. Drying need not be carried to the end point of zero moisture and excellent results are obtained with drying to a residual moisture content of 2-4 percent measured with a resistance type moisture measuring device. Of course the fabric can be bone dried if desired.

The process of the present invention imparts better whiteness retention to cellulosic fabrics, e.g. viscose rayon and cotton fabrics and fabrics containing blends of synthetic and cellulosic fibers. Greatly reduced swelling properties are also imparted to cellulosic fabrics either alone or blended with synthetic fibers. The reaction occurs rapidly so that the cellulosic fibers are not collapsed or highly swollen but are in their normal state. if the fibers were collapsed before the curing with the formaldehyde there would be a reduction in regain and an embrittlement of the fibers.

The present treatment also eliminates the chlorine pickup encountered when cellulose fabrics are treated with aminoplasts including formaldehyde-carbamate resins to bond nitrogen to the cellulose through methylene bridges.

The cellulose fabrics treated according to the invention are extremely durable to laundering and retain wash-wear properties for extended periods of time.

As the hexitol or pentitol formaldehyde scavenger there can be used mannitol, sorbitol, arabitol, xylitol, heptitols, rhamnitol, or mixtures such as Sutro l70-D which is hydrogenated invert sugar. This latter mixture has the same effect as mannitol and a much greater efiect than sorbitol yet costs about onetenth as much as mannitol. Commercially available polyols may also be used.

Conventional surfactants can be added to get good penetration of the fabrics.

The preferred buffer system contains monosodium phosphate and trisodium phosphate. The ratio of monosodium phosphate to trisodium phosphate can range from 1:1 to i021 A portion of the monosodium phosphate, e.g. up to 50 percent, can be replaced by disodium phosphate. When employing paraformaldehyde it is desirable to employ the trisodium phosphate but when employing formalin disodium phosphate can be used to replace the trisodium phosphate. There can also be employed tetrasodium pyrophosphate and sodium tripolyphosphate but they are not as effective as the mixture of monosodium phosphate and trisodium phosphate. The corresponding potassium compounds can be used in place of the sodium compounds. Thus there can be used monopotassium phosphate, dipotassium phosphate and tripotassium phosphate.

Sodium bisulfite can be employed to reduce the formaldehyde odor and to aid in preventing yellowing. It is employed in an amount of from 0.25 percent of the aqueous mix up to one part for two arts of formaldehyde. As stated it can be omitted, particularly with industrial fabrics which do not require as outstanding properties as better quality fabrics. in place of sodium bisulfite there can be used potassium bisulfite, sodium sulfite, potassium sulfite. sodium metabisulfite, sodium bisulfite-acetone.

When tetrasodium pyrophosphate is employed there is a tendency to precipitate magnesium pyrophosphate from the mix if magnesium salts, e.g. magnesium chloride, are employed unless the tetrasodium pyrophosphate and glycolic acid are added prior to the magnesium salts.

While the buffer is employed to increase the pH, normally it is not raised above about a pH of 7. When dimethylsulfone is employed to bring the pH from the acid side up to 7, it is used in an amount of 0.1 to 5 percent of the total mix. The use of higher amounts is not precluded but is wasteful of an expensive material. For one type of fabric, when impregnated fabric is dried in a tenter, the first 25 seconds is for drying and only the last 5 seconds are required for the formaldehyde reaction. Ammonium salts. e.g. ammonium chloride. can be used in place of the metal salt.

Based on the total weight of the aqueous mixture the following table gives the usual range of materials:

TABLE 1 Trisodium phosphate (as tl e decahydrate,

percent 0. 1-0. 75 Paraformaldehyde, percent 1. 5-15 Monosodium phosphate, percent 0. 1-1 Sodium bisulfite (can be omitted) 0. 25

to of the formaldehyde Sutro -D or other hesitol (can be Higher amounts of glycolic acid and the salt can be added but no extra advantage is gained to justify the increase in cost.

The surfactants and softeners used in the examples below are identified as follows.

Surfactant FW is a wetting agent of the ethylene oxide condensate type. It can be replaced by an equal weight of nonylphenol-ethylene oxide condensate having 10 ethylene oxide units in any examples in which Surfactant FW is employed. Any nonionic or anionic surfactant can be used which doesn't precipitate the salt, e.g. magnesium chloride is used.

Mykon SF is polyethylene emulsified in water, 30 percent solids.

Finish No. 4 is a softener emulsion of a higher fatty acid ester made by Proctor and Gamble. It can be replaced by glycerol monostearate.

Except as noted, the process is normally carried out as a one step operation.

Appearance ratings are according to the American Association of Textile Chemists and Colorists (AATCC) Test Method 88-A-l964T-Procedure lll C-l wherein l is the poorest appearance.

EXAMPLE l The procedure employed was to pad the aqueous mixture on the white twill cotton fabric (8 oz./sq. yd.), dry at 270 F. for 4 minutes and evaluate for wash-wear properties. The appearance, shrinkage, nitrogen and formaldehyde were measured afier five home launderings. All of the mixes had a pH between 2.4 and 2.8. Under each mixture number is the parts of carbamate employed.

TABLE 2 Sample Number C urbamate Methyl Methoxycthyl Hydroxypropyl Hydroxyethyl Hydroxypropyl) Hydroxyethyl) TABLE 3 Grab breaking Percent strength fixed Percent (lbs,/ln,) formalde- Percent Appearwarp warp times Sample hyde nitrogen ance shrinkage filling Control O. 08 1. 0 7. 1 168x100 0. 4 0. 13 4. 6 2. 2 109x50 0.72 0. 17 2. 3 104X54 0.76 0. 21 2. 2 108x58 0.70 0.11 2.3 100x51 0.72 0. 2. 1 110x54 0.76 0. 17 2.0 108x58 0. 74 0.12 1. 7 106x56 0. 82 0. 17 1. 9 10BX58 0. 86 0. 21 1. 8 108X58 0.76 0. 12 2. 0 104x64 0. S0 0. 19 1. 9 0BX63 0.84 0. 20 1.!) 106X61 0.70 0.1.! 2.1 102X6-l 0. 76 0. 16 2. 0 108x56 0. 80 0. 21 2. 0 10BX63 EXAMPLE 2 The fabric employed was polyethylene terephthalateviscose rayon. The formulation employed was as follows:

TABLE 4 Concentration Weight/ weight, Component 200 gal. mix percent Trisodium phosphate 3. 5 1 0. 2 Paraformaldehyde 100 6. 0 Monosodium phosphate. 8. 5 0.5 Sodium bisulfite 12.5 0. 75 Dimethyl sull'one 4. 0 0. 25 Methyl carbamate. 16. 5 1. 00 Glycolic acid, 70% l7. 5 1 0. 76 magnesium chloride 53 3 1. 00' Sutro 170 D. 50 3.00 Surfactant FW 3. 5 0. 2 Mykon SF 33 2.0 Procter & Gamble Finish N o. -l 33 2.0

Water sufiicient to make 200 gallo 1 As decahydrate. 2 As glycolic acid. 3 As MgClz.

The mix was prepared as follows. 50 gallons of water was heated to 160 F. Then the trisodium phosphate decahydrate was dissolved therein. The paraformaldehyde was added at 160 F. The mixture was diluted to 100 gallons and then the monosodium phosphate, sodium bisulfite. dimethyl sulfone. methyl carbamate, glycolic acid. magnesium chloride. Sutro l70-D added in order with stirring. The mixture was diluted to 180 gallons and temperature brought to l00l 10 F. Surfactant FW, Mykon SF and Proctor and Gamble Finish No. 4 was added with stirring. The mixture was diluted to 200 gallons.

The mixture is applied to the fabric and the fabric dried at a frame temperature of about 330 F. The fabric temperature is about 240280 F. The amount of formaldehyde fixed was about 0.8 percent.

EXAMPLE 3 The procedure of example 2 was repeated using polyethylene terephthalate/cotton blend (50:50) sheeting. The amount of paraformaldehyde was reduced to 60 pounds (3.3 percent) but all other components were unchanged except for the use of slightly more water to bring the mix to 200 gallons.

EXAMPLE 4 65 percent polyester (polyethylene terephthalate) 35 percent cotton broadcloth shirting fabrics were passed through the following mix in which percentages are by weight of the total mix.

TABLE 5 I Polyvinyl alcohol 0.5%

In a continuous operation the fabrics were padded through the mix and dried in a tenter dryer under the following conditions.

Dryer temperature 3 l 8-33li F. Operating speed yards/min. Total dwell time in drying 15 seconds Fabric temperature at the 255-260 F.

exit end of the dryer as measured with an optical pyrometcr Portions of fabric were taken at this point for testing. They are designated with an A in the table below. The balance of the fabrics were given an alkaline process wash, dried and then treated in the following mix.

Borax 0.5% Sodium bisulfitc 1.5% Zinc fluoboratc 1.0% Ethylene oxide condensate 0.25% (wetting agent) Fatty ester dispersion 3.0% (softener) Water balance The fabric was padded through the mix and dried in a tenter dryer. Conditions for this application were Dryer temperature 250-260 F. Operating speed 1 10 yards/min. Totul dwell time in drying 14 seconds Fabric temperature at the F.

exit end of the dryer 1 Indicates the sample was pressed in a garment press for 15 seconds including 5 seconds steaming, 5 seconds.

1 None found.

heating at a steam pressure of 100 p.s.i.g. and 5 seconds- EXAMPLE 6 Using several different buffers, 9 inches warpwise strips cut from 48 inches 1.39 yd./lb. cotton twill fabric was padded with the mixes and vacuum extracted, dried and cured in an oven at 330 F. 1,000 4 minutes.

All of the samples contained I00 grams of 10 percent methyl carbamate in water and I08 grams of 37 percent aqueous formaldehyde. All samples also contained sufficient water to make the samples up to i000 grams. Samples 1-15 contained 32 grams of 30 percent magnesium chloride and sample 22 contained 28 grams of 30 percent magnesium chloride.

t f Samples 16-19 contained 28 grams of 30 percent magnesium vacuum ex rac ion.

. chionde. Samples 16-19 contained [5 grams of zinc nitrate Shms were ade from. Samples 2A and m bemg hexahydrate, samples 20 and 2i contained 120 grams ofS perlaundered 50 times the shirts were analyzed for nitrogen and cent aqueous zinc fluoborate p 1 21 comained 76 formaldehyde. For comparison a Manhattan Shirt Company 65 percent polyester polyethylene terephthalate), 35 percent 20 2 g ff g glfi gg ir ggiifg fgfg cotton broadcloth shirt indicated to be treated with a carbag d 21 d y f p mate-formaldehyde precondensate was analyzed after 50 comame grams percent aqueous so launders blsulfite and sample 22 contained 75 grams of 10 percent aqueous sodium blsulfite. The samples also contained the in- TABLE 7 (after 50 launders) 25 gredients set forth in the table and the indicated properties.

Sample 2 Nitrogen k Formaldehyde Formaldehyde to Nitrogen ratio 2A 0.04 0.58 6.11 TABLE 10 28 0.04 0.58 as 30 Amount Mix Fabric M anhattan 0.44 L30 L38 p e g ed e (g p p 1 7 3'2 2'2 EXAMPLE 5 5 aqueous 1 5 Na PO, a2 2.2 4.2 The fabric employed was a cotton twill dyed and prepared 4 figgg fligg 180 for treatment. The mixes employed were as follows. The solu- 5 5% sodium hexatneta- 337 2.3 4. 2 tions of materials employed to make the mix. e.g. 10 percent g gigg 186 2 to methyl carbamate, were solutions in water. (Nit-21 402101120)- 7 222 s a S0 umme 851 C3 0-.. v TABLE 8 4O 9 5%; sodium silicate 89 2.1 4. 1

(commercial) 20 2.4 4.3 p Base Mix Post Catalyst Mix gs;

A B c o E v 10% methyl carbamalc 100 25 31 3s 44 so 13 5% ggg fi 7 3 ehyde 10s 21 34 41 41 $4 14 6 40 2'7 4'4 magnesium de 28 28 28 28 28 28 15 n, 243 7 3,9 10% glycoiic acid s1 s3 s3 83 x: as 16 5% sodium trip0ly- 180 2.9 4.1 10% sodium bisuifitc 7s 7s 1s 7s 7s 7s 17 gyg i 62 1 4 1 S'itctrasodium pyrophosphalc 75 75 75 75 75 75 r 0 01103.61 102 SurfuctaniFW 20 2o 20 2o 20 2o 3- 2Z 228 metasmcate g g'g Rhupicx 5-32 22 25 boric 56'6"" 2. 2 3.6 Water to make 1.000 parts in all mixes 5O 21" 4 4 2 The procedure was to pad the base mix on at room temperature and vacuum extract. Then the fabric was dried in a 250 F. oven to obtain a fabric temperature of l60170 F. and 55 then the fabric was cured at 230 F. for 20 minutes. Next it TABLE 11 was given an X-0' (sodium meta bisulfite treatment as set Percent formaldeh d8 Grab forth in Waddle US. Pat. 2,870,04l) treatment at 180 F., Warp strength washed twice at 140 F. and dried in an oven at 250 F., Sam 16 Ori inal f f g g f ggfigig washed twice at i40 F. and dried in an oven at 250 F. to a 60 p g p abric emperature of l60l70 F. Next the post catalyst mix Control 8. 7 g Hggg was applied, the fabric vacuum extracted and dried in a 250 0: 78 0:57 1144 98x59 F. oven to a fabric temperature of l60l70 F. 3. 7g 8.2% 1: gggi The treated fabrics along with a control (untreated) sample 67 53 1: 94 115x68 of the fabric were then tested. The results are set forth below. 8- a 3 5- 2% 5x22 01 s4 0: s9 01 96x52 TABLE 9 O. 10 0.61 0. 72 82X51 0. 71 0. 53 1. 11 101x61 Grab strength 0. 92 0. 73 0.47 74x61 Percent Obs.) after 0. 68 0.21 I). 67 64X35 Appearance Crease shrinkage, 5 home 0. 78 0.67 1.06 27x46 Sample rating rating warp launderings 3. :4]: 3. Z} i1). 33 I 2. 7 1. 0 6. 25 150x139 0. 70 0. 28 2. 66 149x34 i. g 2.1; 1. 8 x95 0.62 0. 39 8 3 1. 8 100x102 0. 72 0.38 4. 6 4. 6 1.8 99x97 0.78 0. 62 1. 33 x63 4. 2 4. 3 1.8 103x98 0. 72 0. 28 2. 66 153x92 4. 3 4. 1 2. 0 108x105 0. 92 0. 62 1. 11 100x50 9 EXAMPLE 7 EXAMPLE 9 The following formulations were made and the bufi'ered A series of i8 samples were prepared using the formulations solutions prepared were padded on 65 percent polyester, 35 in the table- The Solutions made P to 2,000 grams were percent cotton twill fabric and dried at 350 F. for 1.5 5 padded n 67 p r n viscose r y 33 p r n cotton minutes. tablecloth fabric and dried at 350 F. (oven temperature) for L5 minutes to obtain a fabric temperature of 2 9 2-294F TABLE 16 Sample Material 1 2 3 4 5 6 7 8 9 1O 11 12 13 14 15 16 17 18 37% formaldehyde 217 217 217 217 217 217 217 217 217 217 217 217 217 326 217 217 217 217 Methyl carbamate. 2O 20 20 20 20 20 20 20 20 20 2 20 20 20 20 20 20 20 0 10% NBHSOg. 150 150 150 150 150 150 150 150 150 120 90 60 30 150 150 150 150 150 Sutro 170D 6O 60 60 60 60 60 60 60 60 60 60 60 6O 60 40 20 10% glycolic acid 100 100 100 100 100 80 60 40 20 80 80 80 80 80 80 80 80 80 Mg C11, 307 56 56 56 56 56 56 56 56 56 56 56 56 56 56 56 10% N aHiPO4 100 80 60 40 20 40 40 40 40 40 40 40 40 40 40 40 40 40 10% surfactant FW 40 40 40 40 40 40 40 40 40 40 40 40 40 40 40 TABLE 12 TABLE 17 1 2 3 4 5 6 7 8 9 20 Percent formalde- Percent Material, grams: Mix pH Fabric pH hydefixed shrinkage %formaldehyde 217 217 217 217 217 217 217 217 217 Methyl carbamate. 20 20 20 20 20 20 20 20 20 Sample: 10% sodium bisulfite. 350 350 350 150 150 150 150 150 150 1 2.5 4. 3 0. 94 5. 78 Mannitol 60 50 60 50 60 60 60 e0 2 2. 5 4. 3 0. 96 5. 56 10% glycollc acid 166 166 166 166 166 166 166 150 100 3 2. 4 4. 3 0. 94 5. 56 magnesium chlo- 4. 2. 4 4. 3 0. 88 5. 50 ride 56 56 56 56 56 56 56 56 56 5 2. a 4.1 0.88 6. 23 1 NBH2PO4. 50 100 50 100 100 100 100 6, 2.2 4.3 1. 02 6- 2 50 50 7 2. 3 4. 5 0. 96 6. 23 50 50 50 50 50 50 50 50 50 s. 2. 4 4. 8 o. 90 6. 39 50% Sol'bitol 120 0 2. 6 5. 1 0. 70 8. 7 Water balance to make 10 2. 0 4. 3 1. 14 7 2.000 grams in each of IL 2. 1 4. 2 1. 28 4. 38 samples 1-9. 12 2.1 4. 1 1. 28 4.16 R 13 2.1 4. 0 1. 48 3.27

14 2. 2 4. 2 g: l5 2. 2 4. 2 16 Percent Colorimetric 17 2 formaldeodor ratin Percent g hyde after (AAIC Warp Umteatei Sample 5 launders Fabric pH 113-19651) shrinkage v .7 e 1... 0.56 5.9 0.5 1.2 2 0. 50 5. 7 1. 0 1. a 0. 60 5. 2 0. 5 1.; EXAMPLE [0 4 0. 52 4. 5 1. 0 1. 5 0. 4. 4 1. 5 1,1 The following mixes (all parts are in grams) were padded on g" 8- S8 i-g a rayon-cotton tablecloth fabric at room temperature. The 8:: l 0: 7o 4: 5 2: o 1: c fabric was then dried at 330 F. (oven temperature) for 1.5 9 0.54 5.4 2.5 1.0 minutes in W EXAMPLE 8 TABLE 18 Sodium hexametaphosphate employed as a buffer in the Sample following formulations. The mixes were padded on (a) a cot- 4 ton twill fabric and (b) a 50 percent polyester, 50 percent cot- I 2 3 ton twill fabric. The cotton twill fabric was dried at 350 F. for 50 m dal: l h 2 2 7 217 217 L5 minutes and the polyester, cotton twill fabric was dried at flfg gifigg fiig $5 20 20 350 F. for 2 minutes. To simulate usual procedure for durable Sodium bilslllfiten 1 150 150 150 50% sutro 170 D 120 120 120 120 press garment manufacture. the treated fabrics were creased 10% glycouc 80 80 80 80 by pressing 15 seconds at l20 p.s.i.g. steam pressure in a garmagnesium filwbome- 49 35 24 12 o 55 10% Na zPOr 40 40 40 40 mem p e s and heated in an oven at 325 F. for 8 minutes. 10% Surfactant Fw 4o 40 40 40 Water sufllclent tomake 2000 grams TABLE 14 in all samples.

1 2 3 e Material, grams:

37% formaldehyde 217 217 217 EXAMPLE 1 1 Methyl carbamatm 2O 20 20 53 539;? blsulfite 28 gg gg The following mixes were padded on a bleached 50 percent 10%;, fillytollic aeid I 100 100 100 polyester 50 pecent cotton fabric at room temperature and 0 g 2 56 56 56 O v Sodium hexametap 40 100 200 dried in an oven (a) at 630 F. for 1 minute and (b) at 330 F. 10% surfactant FW 50 5c 5 for 1.5 minutes. The mixes all contained enough added water Water sufficient to make 2000 grams...

to make a total of 2,000 grams of mix.

TABLE 15 Cotton twill Tanker twill Control 1 2 3 Control 1 2 3 Percent l1oxumctnpliosphutc.. 25 0. 50 Appearance (5 lauudors) .1 Crenserntlng .8 Fabric pH Fix h kag TABLE 19 Material, grams:

10% monosodium phosphate 100 92 85 77 70 62 92 10% trisodium phosphate.. 76 152 2% 304 380 76 10% sodium bisulfite. 100 100 100 100 100 100 100 Methyl carbamate 20 20 20 20 20 20 20 37% formaldehyde 216 216 216 216 216 216 216 Dimethyl sulfone '20 20 20 20 2O 20 20 10% glycolle acid 100 100 100 100 100 100 100 30% MgCl'. 56 56 56 56 56 56 56 10% Surfactant FW 50 5O 50 50 50 50 50 The results obtained are set forth in the following table.

TABLE 20 330 oven 350 oven Fabric Percent Fabric Percent pH CHzO pH CHzO In the steam tube test for free formaldehyde in which steam is passed through a fabric sample placed in a stainless steel tube in the manner of AATCC Test method 1 l3-l965T and the efi'luent steam is smelled, after the 350 F. oven. treatment sample 1 showed a strong formaldehyde odor, sample 2 a moderate formaldehyde odor and samples 3-7 a slight formaldehyde odor.

EXAMPLE 12 A series of eight mixes were prepared and 50 percent polyester, 50 percent cotton sheeting padded there through at room temperature and dried at 330 F. for 1 minute.

Each mix contained 80 grams of 10 percent monosodium phosphate, 40 grams of percent trisodium phosphate, 200 grams of percent sodium bisulfite, grams of dimethyl sulfone, 216 grams of 37 percent formaldehyde, 120 grams of 50 percent Sutro l70 D l00 grams of 10 percent glycolic acid, 56 grams percent magnesium chloride, 50 grams of 10 percent Surfactant FW, 20 grams of carbamate and water to make 2,000 grams. The carbamates employed were as follows: (1) methyl carbamate, (2) ethyl carbamates, (3) N-ethyl methyl carbamate, (4) N-ethyl ethyl carbamate, (5) N-butyl carbamate, (6) hydroxyethyl carbamate, (7) hydroxypropyl carbamate, (8) hydroxypropyl-hydroxyethyl carbamate mixture. Except for the mix pH all tests were after 5 home launderings. The results are set forth below.

A series of mixes were prepared and 50 percent polyester, 50 percent cotton sheeting padded there through at room temperature and dried at 330 F. for 1 minute.

Each mix contained 80 grams of 10 percent monosodium phosphate. grams of 5 percent trisodium phosphate, 20 grams of dimethyl carbamate, 216 grams of 37 percent formaldehyde, 120 grams of percent Sutro-l70-D, 100 grams of 10 percent glycolic acid, 56 grams of 30 percent magnesium chloride, 50 grams of 10 percent surfactant solution, 10 percent sodium bisulfite and 10 percent dimethyl sulfone (DMS0 in the amounts in grams set forth below and water to make 2,000 grams.

TABLE 22 10% IO% Fabric pH Sample NaHSO, DMSO, Mix pH after drying 1 0 0 2.3 3.90 2 30 0 2.5 3.81 3 60 0 2.7 3.90 4 0 2.8 4.06 5 120 0 2.5 4.20 6 150 0 2.4 4.38 7 0 20 2.5 3.91 8 30 20 2.5 3.91 9 60 20 2.5 4.02 lo 90 20 2.5 4.07 l I 120 20 2.5 4.23 l 2 150 20 2.5 4.42 13 0 40 2.4 3.90

14 30 40 2.4 4.01 15 60 40 2.4 4.04 16 90 40 2.4 4.1" I? 120 40 2.4 4.23 18 150 40 2.5 4.50 19 0 60 24 3,87 20 30 60 2.4 3,90 21 60 60 2.4 4.10 22 90 60 2.4 4.07 23 120 60 2.4 4.25 24 I50 60 2.4 4.61 25 0 2.4 3.88 26 30 100 2.4 3.92 27 60 100 2.7 403 28 90 100 2.5 4.18 29 100 2.5 4.47 30 100 2.4 4.72 31 0 100 2.4 4.00 32 30 200 2.4 4.10 33 60 200 2.4 4.19 34 90 200 2.4 4.22 35 120 200 2.4 4.51 36 I50 200 2.4 5.05

EXAMPLE 14 acid, 56 grams of 30 percent magnesium chloride, 120 grams of 50 percent Sutro l70-D, the indicated amounts of 10 percent dimethyl sulfone and cold water sufficient to make 2,000 grams. The mix was padded on sheeting which was 50 percent cotton-50 percent Dacron (polyethylene terephthalate) at room temperature and dried at 350 F. in an oven for 1 minute. The results are shown in the following table. The percent shrinkage and percent formaldehyde were measured after five launders.

TABLE 23 10'}; dimethyl Percent Percent Fabric suli'one Mix pH shrinkage H7O pH Samples:

A series of runs were made with varying amounts of buffer to raise the pH of the fabric close to neutral. There were employed in the mixes the indicated amount of percent trisodium phosphate, 60 grams of paraformaldehyde, the indicated amounts of percent monosodium phosphate, 150 grams of 10 percent sodium bisulfite, grams of methyl carbamate, 100 grams of 10 percent glycolic acid, 120 grams of 50 percent Sutro 170 D, 50 grams of Surfactant FW and sufficient water to make 2,000 grams. The mixture was padded on 50 percent cotton-50 percent Dacron sheeting at room temperature and the sheeting dried at 350 F. for 1 minute. The pH of the initial mix and fabric pH were measured and the percent shrinkage and percent formaldehyde were measured after five home launders. In this example and the other examples employing trisodium phosphate it was always measured as Na PO,. 12H,O, e.g. if the example states 40 grams of 5 percent trisodium phosphate was used this would means that Na PO,. l2H 0, was dissolved in water to give a 5 percent solution containing 40 grams in all.

14 sodium bisulfite, 20 grams of methyl carbamate, 100 grams of 10 percent glycolic acid, 56 grams of percent magnesium chloride, the indicated amounts of 50 percent Sutro 170 D, 50 grams of 10 percent Surfactant FW and water sufficient to make 2,000 grams. The mix was padded on 50 percent cotton-50 percent Dacron sheeting at room temperature and the fabric dried at 350 F. for 1 minute.

TABLE 27 l 2 a 4 Material Amount Paraformaldehyde 00 6060 37% Fonnaldchyde 163 50% Sutro 170D e0 :20

The properties of the mix and finished fabrics are shown below.

EXAMPLE 18 The purpose of this experiment was to determine the minimum level of formaldehyde in the mix to yield 1 percent formaldehyde fixation. The mixes prepared were padded on 50 percent Dacron50 percent viscose rayon sheeting. All of TABLE 24 5% trlsodlum 10% Percent Percent phosphate N8H2PO4 pH shrinkage CH1O Fabric pH 40 80 2. 1 0. 67 0. 48 5. 42 60 120 2. 3 1. 11 0. 45 e 20 80 160 2. 5 1. 17 0. 40 6. 10 100 200 2. 6 1. 05 0. 41 e 31 100 2. 4 1. 22 0. 48 6.00 150 75 2. 5 1. 11 0. 44 6. 68 200 100 2. 7 l. 17 0. 41 6. 72 250 125 3.0 1. 17 0. 40 6. 9s 4.44 EXAMPLE 16 35 TABLE 28 50 percent Dacron-50 percent cotton sheeting was padded fii L ags: through the mixes set forth below at room temperature and Percent Percent Fabric percent dried at 350 F. for 30 seconds. The mixes contained enough pH shrinkage cmo P water to make 2,000 grams of mix.

1. 0 0.60 4. 39 0. 47 1. 06 0.67 5. 57 0. 53 0. 89 0. 57 3. 89 0. 49 TABLE 25 1.0 0.68 4 00 0. 50 3. 72 0. 41 1 z 3 M t 1 Wei m -T-?,:,, phusphm 250 250 45 the mixes were made up to 2,000 grams. Each mix contained Puraformaldehyde e0 e0 60 80 grams of 5 percent trisodium phosphate, the indicated PlmsPhc amount of paraforrnaldehyde, 100 grams of 10 percent f f 1 monosodium phosphate, 150 grams of 10 percent sodium Glycolic acid .00 200 200 302 Magnesium chloride 1 l2 bisulfite, 5 grams of dimethyl sulfone, 20 grams of methyl car- 1" 1 50 bamate, 150 grams of 10 percent glycolic acid, 67 grams of 30 2g: g no as percent magnesium chloride, 120 grams of 50 percent Sutro 1; swam, Fw 50 50 50 170 D, 40 grams of 10 percent Surfactant FW, 48 grams of Methyl carbamate 40 40 40 The mix pH and fabric pH were determined as well as percent shrinkage and percent formaldehyde afier 5 launders. The results are shown below.

Mixes were prepared containing 40 grams of 5 percent trisodium phosphate, the indicated amounts of paraformaldehyde or 37 percent aqueous formaldehyde, 80 grams of 10 percent monosodium phosphate, 144 grams of 10 percent Mykon SF and 48 grams of Finish No. 4. The mix pH, formaldehyde fixation and fabric pH were recorded. The mix was padded on at room temperature and drying was at 350 F. for 1 minute. 7

The procedure and mixes were the same as in example 18 but the fabric was percent viscose rayon. Samples 1, 2. 3, 4 and 5 had the same materials and proportions as the samples in example 18. The oven dwell times at 350 F. were varied. In the following table the letter A designates 1 minute dwell, the letter B 1.5 minutes dwell and the letter C 2 minutes dwell.

The values were recorded (with the exception of the initial pH of the mix and fabric pH) after launders.

1. in a process of fixing formaldehyde on a hydroxyl containing polymer selected from the group consisting of cellulose, cellulose acetate, cellulose acetate-propionate and cellulose acetate-butyrate by treating said polymer with an aqueous mixture comprising l formaldehyde, (2) a carbarnate having the formula \N C O O R; R.

where R and R are selected from the group consisting of hydrogen, alkyl and carbocyclic aryl and R is selected from the group consisting of alkyl, carbocyclic aryl, hydroxy lower alkyl and lower alkoxy lower alkyl and (3) glycolic acid. the improvement comprising including in the aqueous mixture a buffer to counteract the tendency of the cellulosic material impregnated with said mixture to become highly acidic on standing.

2. A process according to claim 1 wherein the treating solution includes a water soluble salt of a polyvalent metal capable of catalyzing the reaction between cellulose and formaldehyde.

3. A process according to claim 1 wherein the treating solution includes water soluble sugar alcohol selected from the group consisting of pentitols, hexitols and heptitols.

4. A process according to claim 1 wherein the buffer includes an alkali metal phosphate, the aqueous mixture includes alkali metal bisulfite in an amount sufficient to reduce formaldehyde odor and also includes dimethyl sulfone in an amount ofO.l to 5 percent to raise the pH.

5. A process according to claim 1 wherein the polymer is in the form offibers.

6. A process according to claim 1 wherein the buffer includes an alkali metal phosphate.

7. A process according to claim 6 wherein the phosphate comprises monosodium phosphate.

8. A process according to claim 6 wherein the phosphate comprises disodium phosphate.

9. A process according to claim 5 wherein the fibers are in the form of a fabric.

10. A process according to claim 6 wherein the aqueous mixture includes dimethyl sulfone in an amount effective to raise the pH of the treated polymer.

11. A process according to claim 6 wherein the phosphate comprises trisodium phosphate.

12. A process according to claim 11 wherein the phosphate also comprises monosodium phosphate.

13. A process according to claim 6 wherein the aqueous mixture includes alkali metal bisulfite in an amount sufficient to reduce formaldehyde odor.

4. A process according to claim 13 wherein the bisulfite comprises sodium bisulfite.

15. A process according to claim 13 wherein the aqueous mixture includes dimethyl sulfone in an amount effective to raise the pH of the treated polymer.

16. A process according to claim 15 wherein the aqueous mix also contains mannitol as a formaldehyde scavenger and sodium bisulfite to reduce the formaldehyde odor.

17. A process according to claim 6 wherein the aqueous mix also contains sugar alcohol of the group consisting of pentitols, hexitols and hepitols as a formaldehyde scavenger.

18. A process according to claim 17 wherein the sugar a1- cohol comprises mannitol.

19. A process according to claim 16 wherein the carbamate is methyl carbamate.

20. A process according to claim 18 wherein the treating mixture comprises 0.1 to 0.75 percent trisodium phosphate calculated as the decahydrate, 1.5 to 15 percent formaldehyde, 0.1 to 1 percent monosodium phosphate, sodium bisulfite in an amount of 0.25 percent to not more than l part for each two parts formaldehyde, 0.1 to 5 percent of the carbamate, 0.1 to 1.5 percent of glycolic acid.

21. A process according to claim 1 comprising treating a cellulose fabric with an aqueous mixture of l formaldehyde, (2) methyl carbamate or ethyl carbamate, glycolic acid and an alkali metal phosphate buffer.

22. A process according to claim 21 wherein the buffer comprises monosodium phosphate.

23. A process according to claim 22 wherein the buffer includes trisodium phosphate.

24. A process according to claim 22 wherein the aqueous mixture also contains sodium bisulfite, magnesium chloride, dimethyl sulfone and mannitol.

25. A process according to claim 23 wherein the ratio of monosodium phosphate to trisodium phosphate is between 1:1 and 10:1.

26. A process according to claim 25 wherein the treating solution includes 0.! to 2.5 percent of magnesium chloride.

0: II! =0 l 

2. A process according to claim 1 wherein the treating solution includes a water soluble salt of a polyvalent metal capable of catalyzing the reaction between cellulose and formaldehyde.
 3. A process according to claim 1 wherein the treating solution includes water soluble sugar alcohol selected from the group consisting of pentitols, hexitols and heptitols.
 4. A process according to claim 1 wherein the buffer includes an alkali metal phosphate, the aqueous mixture includes alkali metal bisulfite in an amount sufficient to reduce formaldehyde odor and also includes dimethyl sulfone in an amount of 0.1 to 5 percent to raise the pH.
 5. A process according to claim 1 wherein the polymer is in the form of fibers.
 6. A process according to claim 1 wherein the buffer includes an alkali metal phosphate.
 7. A process according to claim 6 wherein the phosphate comprises monosodium phosphate.
 8. A process according to claim 6 wherein the phosphate comprises disodium phosphate.
 9. A process according to claim 5 wherein the fibers are in the form of a fabric.
 10. A process according to claim 6 wherein the aqueous mixture includes dimethyl sulfone in an amount effective to raise the pH of the treated polymer.
 11. A process according to claim 6 wherein the phosphate comprises trisodium phosphate.
 12. A process according to claim 11 wherein the phosphate also comprises monosodium phosphate.
 13. A process according to claim 6 wherein the aqueous mixture includes alkali metal bisulfite in an amount sufficient to reduce formaldehyde odor.
 14. A process according to claim 13 wherein the bisulfite comprises sodium bisulfite.
 15. A process according to claim 13 wherein the aqueous mixture includes dimethyl sulfone in an amount effective to raise the pH of the treated polymer.
 16. A process according to claim 15 wherein the aqueous mix also contains mannitol as a formaldehyde scavenger and sodium bisulfite to reduce the formaldehyde odor.
 17. A process according to claim 6 wherein the aqueous mix also contains sugar alcohol of the group consisting of pentitols, hexitols and hepitols as a formaldehyde scavenger.
 18. A process according to claim 17 wherein the sugar alcohol comprises mannitol.
 19. A process according to claim 16 wherein the carbamate is methyl carbamate.
 20. A process according to claim 18 wherein the treating mixture comprises 0.1 to 0.75 percent trisodium phosphate calculated as the decahydrate, 1.5 to 15 percent formaldehyde, 0.1 to 1 percent monosodium phosphate, sodium bisulfite in an amount of 0.25 percent to not more than 1 part for each two parts formaldehyde, 0.1 to 5 percent of the carbamate, 0.1 to 1.5 percent of glycolic acid.
 21. A process according to claim 1 comprising treating a cellulose fabric with an aqueous mixture of (1) formaldehyde, (2) methyl carbamate or ethyl cArbamate, glycolic acid and an alkali metal phosphate buffer.
 22. A process according to claim 21 wherein the buffer comprises monosodium phosphate.
 23. A process according to claim 22 wherein the buffer includes trisodium phosphate.
 24. A process according to claim 22 wherein the aqueous mixture also contains sodium bisulfite, magnesium chloride, dimethyl sulfone and mannitol.
 25. A process according to claim 23 wherein the ratio of monosodium phosphate to trisodium phosphate is between 1:1 and 10:1.
 26. A process according to claim 25 wherein the treating solution includes 0.1 to 2.5 percent of magnesium chloride. 